12x8 meters? :) I'm assuming you mean 12x8 feet. I have Sonatina IIIs in a 13x17x10h room and I don't feel I'm missing any bass from the speakers or have too much. I drive them with Manley Snappers. I auditioned the Sonata IIIs (great speakers) in a much bigger room (dealer didn't have Sonatinas) and his concern was they might be too much for my room. He did ask Alan Yun and Alan said that the Sonatas could be fine depending on how they were driven and type of music. I went with the Sonatinas and have not regretted it. I wouldn't mind hearing how the Sonatas sound in my room though. :)
Your room is much smaller. The Sonatinas are great sounding speakers, but they are rear ported which could cause issues in your room wrt placement - they may need to be too far from the wall to get bass right. You may want to consider a front ported speaker or monitors and a small sub.
Good luck.
larry
